From 2366c7fdb59812bbd1382afed69e250582c64187 Mon Sep 17 00:00:00 2001 From: Shannon Zhao Date: Thu, 7 Apr 2016 20:03:29 +0800 Subject: [PATCH] ARM64: ACPI: Check if it runs on Xen to enable or disable ACPI When it's a Xen domain0 booting with ACPI, it will supply a /chosen and a /hypervisor node in DT. So check if it needs to enable ACPI. Signed-off-by: Shannon Zhao Reviewed-by: Stefano Stabellini Acked-by: Hanjun Guo Tested-by: Julien Grall Acked-by: Mark Rutland Acked-by: Catalin Marinas Signed-off-by: Will Deacon --- arch/arm64/kernel/acpi.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c index d1ce8e2..57ee317 100644 --- a/arch/arm64/kernel/acpi.c +++ b/arch/arm64/kernel/acpi.c @@ -67,10 +67,15 @@ static int __init dt_scan_depth1_nodes(unsigned long node, { /* * Return 1 as soon as we encounter a node at depth 1 that is - * not the /chosen node. + * not the /chosen node, or /hypervisor node with compatible + * string "xen,xen". */ - if (depth == 1 && (strcmp(uname, "chosen") != 0)) - return 1; + if (depth == 1 && (strcmp(uname, "chosen") != 0)) { + if (strcmp(uname, "hypervisor") != 0 || + !of_flat_dt_is_compatible(node, "xen,xen")) + return 1; + } + return 0; } @@ -184,7 +189,8 @@ void __init acpi_boot_table_init(void) /* * Enable ACPI instead of device tree unless * - ACPI has been disabled explicitly (acpi=off), or - * - the device tree is not empty (it has more than just a /chosen node) + * - the device tree is not empty (it has more than just a /chosen node, + * and a /hypervisor node when running on Xen) * and ACPI has not been force enabled (acpi=force) */ if (param_acpi_off || -- 2.7.4